CN1223887C

CN1223887C - Method for making liquid crystal display screen

Info

Publication number: CN1223887C
Application number: CNB021190135A
Authority: CN
Inventors: 朴武烈; 丁圣守
Original assignee: LG Philips LCD Co Ltd
Current assignee: LG Display Co Ltd
Priority date: 2002-03-07
Filing date: 2002-04-29
Publication date: 2005-10-19
Anticipated expiration: 2022-04-29
Also published as: KR20030072826A; US6738124B2; JP4131489B2; US20040127136A1; CN1444080A; JP2003270645A; US7532301B2; US20030169393A1; KR100662495B1

Abstract

A method for fabricating a liquid crystal display panel includes forming closed main UV sealant on either one of first and second substrates, and forming a dummy UV hardening sealant is coated on the area surrounding the main UV hardening sealant; forming a liquid crystal layer between the first and second substrates; attaching the first and second substrates; irradiating a UV ray on the attached substrates with masking regions where the dummy UV sealant and at least one scribing line are crossed to attach the said two substrates; and cutting the bonded substrates into a plurality of unit cells.

Description

A kind of method of making LCDs

The application requires the rights and interests of the No.P2002-12056 korean patent application of on March 7th, 2002 application, and described korean patent application is in this article with the in addition combination of the form quoted.

Technical field

The present invention relates to LCD, or rather, relate to add the method for manufactured LCD (LCD) screen with liquid crystal drop.

Background technology

Thin flat panel type display often has and is not more than several centimetres thickness.Particularly, LCD (LCD) has purposes widely, as is used for notebook computer, graphoscope, the instrument display monitor central monitoring system of spacecraft and aircraft etc.

In general, LCD is provided with: a following substrate forms thin film transistor (TFT) and pixel electrode on it; Go up substrate for one, relative with following substrate, form black matrix (black matrix), colour filter, and common electrode on it; And a liquid crystal layer between described two substrates, described liquid crystal layer drives liquid crystal by the electric field that is applied to pixel electrode between the substrate and the electricity on the common electrode and produces, regulating the transmissivity of liquid crystal, thereby on display screen displayed image.

In above-mentioned LCD, at present normally used is vacuum impregnation, to form liquid crystal layer between the substrate up and down.In such method, after will descending substrate and last substrate to be bonded together, utilize capillarity and pressure reduction between described two substrates, to inject liquid crystal.But described vacuum impregnation injects liquid crystal between substrate will spend long time.The result is along with substrate becomes conference throughput rate obviously to be lowered.

Therefore, in order to address the above problem a kind of method that is referred to as the liquid crystal drop addition that proposed.Explanation uses the liquid crystal drop of prior art to add the method for manufactured LCD display with reference to the accompanying drawings.

Figure 1A-1E represents to use the liquid crystal drop of prior art to add the expansion skeleton view of the method for manufactured LCD display.For convenience's sake, four unit boxes only are shown in the drawings.

Referring to Figure 1A, its preparation be following substrate 1 and last substrate 3 in this operation.Down forming many grid (gate) lines and data line (all not shown) on the substrate 1, their formation pixel regions that intersects each other.On each intersection point of described gate line and data line, form a thin film transistor (TFT).On each pixel region that connects described thin film transistor (TFT), form a pixel electrode.

On last substrate 3, form black matrix, shield from gate line the light of data line and TFT regions seepage.Form red, green and blue look colour filter on the black matrix.On colour filter, form common electrode then in regular turn.Forming the oriented film that makes the liquid crystal initial orientation on substrate 1 and the last substrate 3 down.

In Figure 1B, down applying primary seal agent 7 and virtual area (dummy) sealant 8 on the substrate, and a plurality of liquid crystal drop 5 is positioned at down on the substrate, with the formation liquid crystal layer.Then, on last substrate 3, scatter wadding (spacer), to keep the box gap.

Primary seal agent 7 is in order to preventing liquid crystal leakage, and substrate is bonding up and down.Sealant 8 on the virtual area is formed on the virtual area in primary seal agent 7 outsides.The effect of virtual area sealant 8 is protection primary seal agent 7.

Splash in the method at such liquid crystal, need before sealant cures, with liquid crystal place be attached together up and down between the substrate.Therefore, if use the bonding described substrate of thermal cure sealants, sealant can flow and pollute liquid crystal in heating process.Therefore, must use ultraviolet ray (UV) sealant to avoid this type of problem.

Referring to Fig. 1 C, following substrate 1 is attached to each other with last substrate 3 and is in the same place.Shown in Fig. 1 D, use UV radiation appliance 9 irradiation UV rays to come curing sealant 7 (being shown in Figure 1B), thereby will descend substrate 1 and last substrate 3 bonding.Substrate 1 and substrate 3 that Fig. 1 E shows after bonding are cut into a plurality of unit liquid crystal cell.

Fig. 2 represents substrate is cut into the operation of a plurality of unit liquid crystal cell.In Fig. 2, use a scriber, on the surface of bonding substrate 1 and substrate 3, form line (crossed process), described scriber for example is to have the diamond pen bigger than the hardness of backing material glass.Then, apply physical shock (sliver operation) along line 10, to be cut to a plurality of unit liquid crystal cell.In addition, also can in an operation, use diamond pen or wheel, carry out described crossed process and sliver operation, thereby obtain described unit one by one.

Fig. 2 represents the cutting action of liquid crystal cell, wherein is not shown specifically line.In actual liquid crystal cell cutting action, also can form more line, thereby will remove at the virtual area in the box outside.

Fig. 3 shows in detail the planimetric map of line.Particularly, express the sealant 7 and 8 that on following substrate 1, forms with line 10.

Referring to Fig. 3, before the liquid crystal cell cutting action, when solidifying virtual area sealant 8 by the UV irradiation process, on the zone shown in the circle, line 10 is overlapping with the part of virtual area sealant 8.

Therefore, when ruling with sliver acquisition unit liquid crystal cell one by one, the virtual area sealant 8 of sclerosis does not make the unit liquid crystal cell go wrong.But, rule at the same time and sliver and when one by one obtaining the unit liquid crystal cell, because virtual area sealant 8 causes of solidifying, it is difficult cutting into the unit liquid crystal cell.

Summary of the invention

Therefore, the purpose of this invention is to provide a kind of method of making LCDs, in fact it avoided the one or more problems that limitation and shortcoming caused because of prior art.

Another object of the present invention provides a kind of method of making LCDs, it rule at the same time and the process of sliver in make the cutting of liquid crystal cell become to be easy to.

Other features and advantages of the present invention can be by manifesting in the following explanation, and Partial Feature and advantage can obviously draw from instructions, or obtain by practice of the present invention.To make purpose of the present invention and other advantages be achieved by the structure that in instructions of the present invention, in claims and the accompanying drawing, particularly points out.

In order to realize these and other advantages of the present invention, and according to purpose of the present invention, as recapitulative and bright in a broad sense, the method for described manufacturing LCDs comprises: form the main UV sealant that surrounds a plurality of unit liquid crystal cell on one of first and second substrates; Form virtual area UV sealant in the outside of main UV sealant; Go up at least one dropping liquid crystalline substance of dropping to one of first and second substrates; First and second substrates are attached together; Having irradiation UV ray on the substrate that is attached together of masked area, thereby described two substrates are bonding, described masked area is the infall of virtual area UV sealant and at least one line; With bonding substrate is cut into a plurality of unit liquid crystal cell.

Should be understood that top generality explanation and following detailed description are exemplary and indicative, its purpose is to further specify claim of the present invention.

Brief description of drawings

The accompanying drawing that the application comprised is used for further understanding of the present invention, and it combines with the application, and constitutes the application's a part, and described accompanying drawing is represented embodiments of the invention, and with instructions principle of the present invention is described.

In the accompanying drawing:

Figure 1A-1E is to use the liquid crystal drop of prior art to add the expansion skeleton view of manufactured LCD display method;

Fig. 2 is the skeleton view of liquid crystal cell cutting action in the expression prior art;

Fig. 3 is illustrated in to form many line and sealant planimetric map on the following substrate of prior art;

Fig. 4 A-4E is the expansion skeleton view of expression according to the described manufacturing LCD display of first embodiment of the invention method; With

Fig. 5 A-5C is a skeleton view of representing UV irradiation process in the described according to a second embodiment of the present invention manufacturing LCD method.

Specific embodiment

Describe embodiments of the invention now in detail, the example of these embodiment is shown in the drawings.In each figure, represent identical or similar parts with identical reference marker as much as possible.

Fig. 4 A-4E is the expansion skeleton view according to the described manufacturing LCD display of first embodiment of the invention method.Though four unit liquid crystal cells only are shown in the drawings, the number of unit liquid crystal cell can change according to the size of substrate.

Referring to Fig. 4 A, cross at this and to make down substrate 200 and last substrate 300 in operation.Forming many gate lines and data line (all not shown) on the substrate 200 down; these gate lines and the data line qualification pixel region that intersects each other forms thin film transistor (TFT), grid insulating film, semiconductor layer, ohmic contact layer, source/drain electrodes and the protective film with grid on each intersection point of gate line and data line.On each pixel region that connects thin film transistor (TFT), further form pixel electrode.

On pixel electrode, be formed for the orientation film of liquid crystal initial orientation.Described orientation film can be by polyimide, the polyamide-based compound, polyvinyl alcohol (PVA) (PVA), polyamic acid are made by friction (by rubbing), or, make as tygon cinnamate (polyvinvylcinnamate PVCN) and polysiloxane cinnamate (PSCN) by photochromics.In addition, also can select cellulose cinnamate (cellulosecinnamate CelCN) based compound for use with the optical alignment method.

On last substrate 300, form the light that a light shielding film leaks from gate line, data line and TFT regions with shielding.On film, form red, green and blue colour filter.And on colour filter, form common electrode in regular turn.In addition, between described colour filter and common electrode, can form external coating.On common electrode, form orientation film.

Form silver point (Ag) in the following outside of substrate 200, be used for after substrate 200 down and last substrate 300 are bonded to each other, upwards the common electrode on the substrate 300 applies voltage.In addition, also can on last substrate 300, form described silver point.

In the LCD of plane conversion pattern (IPS), with pixel electrode in the same manner by the common electrode that on following substrate, the forms transverse field of inducting.On described substrate, do not form silver point.

Referring to Fig. 4 B, on last substrate 300, apply main UV sealant 700 with the figure that seals, and apply virtual area UV sealant 800 in the outside of primary seal agent 700 in the mode of sealing.Can use the method for sprinkling or the method for serigraphy to apply described sealant.But, because silk screen will contact with substrate, so method for printing screen can damage the orientation film that forms on substrate.In addition, because the consumption of sealant is big on large-sized substrate, so method for printing screen is uneconomic.

Then, 500 of liquid crystal drops on substrate 200 down, are formed liquid crystal layer.Before primary seal agent 700 is solidified, when running into primary seal agent 700, liquid crystal can make that liquid crystal is contaminated.Therefore liquid crystal drop must drip to down the middle part of substrate 200.After primary seal agent 700 was solidified, the liquid crystal drop 500 in the middle part of dropping in is uniformly dispersing lentamente, made liquid crystal evenly distribute on entire substrate with same concentration.

Fig. 4 B is illustrated in down liquid crystal drop 500 and sealant 700 and the sealant 800 that applies on the substrate 200.But as an alternative method in embodiments of the present invention, also can on last substrate 300, form liquid crystal drop 500, and apply UV sealant 700 and UV sealant 800 on the substrate 200 down.

And, also can on same substrate, form liquid crystal drop 500 and UV sealant 700 and UV sealant 800.But,, may be required in and form liquid crystal drop and sealant on the different substrates in order to shorten the time cycle of manufacturing.When liquid crystal drop 500 and UV sealant 700 and sealant 800 are formed on the same substrate, in manufacture process, have the substrate of liquid crystal and sealant and uneven with existing between the substrate of liquid crystal.For example, because liquid crystal and sealant are formed on the same substrate, before substrate was attached to each other, when sealant was contaminated, substrate possibly can't clean.

On any one of two

substrates

200 or 300, can form wadding (spacer), to keep the gap of box.Described wadding can be from the nozzle high-pressure injection to substrate, and described wadding is formed by the globe lining bedding and padding and the solvent that contain debita spissitudo.In addition, also can on some part of the substrate of gate line or data line, form color filter combinde with columns.Large-sized substrate can be used color filter combinde with columns, because for large-sized substrate, the globe lining bedding and padding can cause uneven cel-gap.Color filter combinde with columns can be by the photosensitive organic resin manufacturing.

Referring to Fig. 4 C, will descend substrate 200 to be attached to each other and be in the same place with last substrate 300.Can will go up substrate 300 and following substrate 200 is bonding by following operation.At first, there is the substrate of liquid crystal to place downside with dripping.With another substrate Rotate 180 degree, make the upper side that constitutes by multilayer on this substrate upper surface towards the substrate that is in downside.Then, exert pressure, or the space between two substrates is evacuated, thereby make two substrates be attached to together to the substrate of upside.

Then, referring to Fig. 4 D, the substrate 200 that adheres to and 300 and UV radiation appliance 900 between place a mask 950, shelter the overlapping region between virtual area UV sealant 800 and the line.Then, shine the UV ray thereon.When irradiation UV ray, make monomer or oligomer generation polymerization and curing, thereby will go up substrate 300 and following substrate 200 is bonding.

Cover out the UV ray by the zone that mask 950 is sheltered, make that the virtual area UV sealant in this zone is not cured.Therefore, virtual area UV sealant keeps initial coating state, that is, fluid state is easy to thereby the box cutting action that carries out behind the bonding process is become.

As UV sealant 700 and sealant 800, use be an end and acrylic coupling mutually, the other end and epoxy radicals coupling mutually, and the monomer or the oligomer that mix mutually with initiating agent.Because epoxy radicals and UV ray do not react, thus can be after curing sealant be subjected to UV irradiation, with sealant be heated to about 120 ℃ one hour.But even by thermal treatment the virtual area sealant is solidified equably, curing degree also is lower than 50%, so the virtual area sealant is to the not influence of cutting process of liquid crystal cell.

Fig. 4 E has represented that the substrate with bonding cuts into the process of single liquid crystal cell.In cutting action, use the diamond cut device, as diamond pen or have the wheel of tooth,, 600 cut described liquid crystal cell singly along ruling by the process of line and sliver simultaneously.Use can be rule and the cutter sweep of sliver operation simultaneously, can reduce space and clipping time that device occupies.

Behind cutting action, carry out last inspection (end illustrates).In last inspection, before assembling was cut into the substrate of each unit liquid crystal cell, the duty of pixel determined whether to exist defective when being applied to the voltage on/off of unit liquid crystal cell by check.

Fig. 5 A-5C is the skeleton view that launches, its expression be according to the UV irradiation process in the described manufacturing of the second embodiment of the invention LCD method.Except the UV irradiation process, all manufacture processes are similar to first embodiment.

Rule at the same time and the process of sliver in, when when cutting each substrate from the line beginning along direction up and down on right side or the left-hand end, can remove the virtual area UV sealant on right side or the left side.Therefore, the virtual area UV sealant of removing does not influence later liquid crystal cell cutting process.

Therefore, though in the upper and lower zone of virtual area UV sealant with line overlapping after, or only the left and right side zone of virtual area UV sealant with line overlapping after, irradiation UV ray still can obtain the result identical with the cutting action of sheltering liquid crystal cell.

What Fig. 5 A represented is, with mask 950a only shelter and the situation of ruling the upper and lower zone of virtual area UV sealant overlapping under, the irradiation process of UV.What Fig. 5 B represented is, with mask 950b only shelter and the situation of ruling virtual area UV sealant left and right side zone overlapping under, the irradiation process of UV.Fig. 5 A can be used at first cutting the embodiment of upper and lower end, and Fig. 5 B can be used at first cutting the embodiment of left and right end.

Fig. 5 C represents the skeleton view according to the UV irradiation process in the method for the described manufacturing of second embodiment of the invention LCD.

When UV shone, if UV shines the whole surface of the substrate that is attached to each other, that was petty, and the UV ray can damage the equipment energy characteristic of the thin film transistor (TFT) on the substrate, and changed into the liquid crystal initial orientation and the pre-tilt angle of the orientation film that forms.

Therefore, in Fig. 5 C, the second embodiment of the present invention proposes, mask 950C is being placed between the substrate 200 and substrate 300 and UV irradiation unit 900 that is attached to each other, thereby after being sequestered in each zone and the active region in main UV sealant 700 of virtual area UV sealant 800 and line intersection, carry out the UV irradiation again.

As mentioned above, the advantage of the method for manufacturing LCDs of the present invention is:

Under the situation of sheltering virtual area UV sealant and line intersection region, carry out UV irradiation, cut liquid crystal cell easilier by the operation of line and sliver simultaneously, this is because the still uncured cause of virtual area UV sealant on ruling.

Be sequestered in active area in the main UV sealant with UV irradiation, can prevent the UV ray damage the thin film transistor (TFT) that is formed on the substrate, to the characteristic of film etc.

To those skilled in the art, obviously, under the situation that does not break away from design of the present invention and scope, can carry out various modifications and variations to the method for manufacturing LCD display of the present invention.Therefore, the invention is intended to cover improvement and the modification that falls in appended claim book and the equivalent scope thereof.

Claims

1. method of making LCDs, it is characterized in that: it may further comprise the steps:

Form main UV sealant and the virtual area UV sealant that surrounds a plurality of unit liquid crystal cell on one of first and second substrates, described virtual area UV sealant is formed on the outside of described main UV sealant;

On one of first and second substrates, drip at least one dropping liquid crystalline substance;

Described first and second substrates are attached to together;

Having irradiation UV ray on the substrate that is attached to each other of blasnket area, thus bonding described two substrates, and described blasnket area is the zone that described virtual area UV sealant and at least one line are intersected; With

Two substrate bodies of described combination are cut into a plurality of unit liquid crystal cell.

2. according to the method for claim 1, it is characterized in that: comprised by the described blasnket area of UV radiation exposure, the upper and lower side masked portion of intersection region between virtual area UV sealant and the line.

3. according to the method for claim 1, it is characterized in that: comprised by UV radiation exposure blasnket area, the left and right side masked portion of intersection region between virtual area UV sealant and the line.

4. according to the method for claim 1, it is characterized in that: the blasnket area that on the substrate that is attached to each other, is subjected to the UV radiation exposure, between virtual area UV sealant and line, the upper and lower side masked portion of intersection region, also comprise the active region that is sequestered in the main UV sealant.

5. according to the method for claim 1, it is characterized in that: the blasnket area that on the substrate that is attached to each other, is subjected to the UV radiation exposure, between virtual area UV sealant and line, the left and right side masked portion of intersection region, also comprise the active region that is sequestered in the main UV sealant.

6. according to the method for claim 1, it is characterized in that: also comprise the active region that is sequestered in the main UV sealant.

7. according to the method for claim 1, it is characterized in that: described main UV sealant and virtual area UV sealant are a kind of in the monomer of two ends and acrylic coupling and the oligomer.

8. according to the method for claim 1, it is characterized in that: described main UV sealant and virtual area UV sealant are an end and acrylic coupling, a kind of in the monomer of the other end and epoxy radicals coupling and the oligomer.

9. according to the method for claim 1, it is characterized in that: the substrate that also comprises heating UV radiation exposure, the substrate of described UV radiation exposure has the blasnket area that intersects between virtual area UV sealant and line, wherein main UV sealant and virtual area sealant are an end and acrylic coupling, a kind of in the monomer of the other end and epoxy radicals coupling and the oligomer.

10. according to the method for claim 1, it is characterized in that: described line is formed on the bonding substrate.

11. the method according to claim 1 is characterized in that:, bonding substrate is cut into a plurality of unit liquid crystal cell by ruling simultaneously and the operation of sliver.

12. the method according to claim 1 is characterized in that: also be included in and form at least a color filter combinde with columns on first substrate.

13. the method according to claim 1 is characterized in that: on first substrate, form main UV sealant and virtual area UV sealant, and drop on second substrate to major general's one dropping liquid crystalline substance.